Tension regulator for paper feed rolls



C. J. KERN May 6, 1941.

TENSION REGULATOR FOR PAPER FEED ROLLS 2 Shets-Sheet 1 Filed April 28,1939 Fild April 28, 1959 2 Sheets-Sheet 2 the roll.

Patented May 1941 g 2,241,301 TENSION aacm'roa roa PAPER. FEED normsColts-(1'1. Kern,

Mollie & W! (20.,

Drexei Park, Pa., assignor to The Philadelphia, Pa, :1. corporation ofPennsylvania Application April as, 1939, Serial No. 2mm

This invention relates to automatic brakes for paper feed rolls and, formaintaining a uniform braking resistance to the withdrawal of paper froma roll supplying a press or similar structure to insure proper ten- 1sion at all times on the sheet withdrawn from- News presses andcorresponding structures which require supply rolls of considerablediameter are usually equipped with what is known as a back-stand uponwhich the roll is mounted and from which it is drawn to the press or thelike. Obviously, the tension at which the paper is removed from the rollis important, particu larly in the case of news presses where changes intension will cause a considerable change in register..

Likewise, obviously, the tension of any fixed diameter brake will varyas the diameter of the roll of paper reduces since the leverage armrepresented by the roll radius reduces constantly in ratio to thediameter of the brake. For this reason some means must be provided tocompensate for the reduction in diameter of the roll. All such meanswith which I slderation the fact that such rolls are usually purchasedin quantity and stored in such manner that they become flattened at oneside.

Important objects of the present invention are the provision of aback-stand including braking mechanism which will compensate for thevariation in diameter of the roll and which will not be affected byvariations in the shape thereof to any appreciable extent and in whichthe variation of pressure is determined by a plurality of contactmembers which are so located that a flattened roll will not affect thebraking in the usual manner.

These and other objects I attain by the construction shown in theaccompanying drawings wherein, for the purpose of illustration, I haveshown a preferred embodiment of my invention and wherein:

Fig. 1 is a side elevation partially broken away and partiallydiagrammatic illustrating roll tensioning means constructed inaccordance with my invention;

Fig. 2 is a plan view thereof and Figures 3 and 4 are detail sectionalviews through valves employed in controlling the braking action.

Referring now more particularly to the drawlngs, the numeral Illgenerally designates one of a pair of bearin s for receiving the rollshaft ii of a paper roll l2. Adjacent the illustrated bearam familiarfail to take into conmore particularly, to a means ing it an outboardbearing I3 is provided, this bearing, together with bearing l0, mountinga shaft l4 which, between the bearings l0 and I3, is equipped with abrake drum it having associated therewith a band brake l5 anchored atone end as at I I and having its opposite end connected'at 18 to thepiston IQ of a cylinder 20 hereinafter more particularly to bedescribed. Shaft H at its inner end is equipped with a gear 2! withwhich a pinion 22 on roll shaft i i meshes.

Mounted between a bracket 23 on bearing iii and a further bearingindicated at 24 and parallelihgroll shaft H a pair or shafts 25each'havlng thereon an arm provided with a roll-surfaceengaging portion26 at its free end the arms indicated at 21 and 2-8 extend in oppositedirections about the roll engaging the periphery thereof at points whichare well spaced circumferentially. These shafts are geared to oneanother by gears 28 of equal size and one of the shafts has attachedthereto a counterweighted arm 30 so arranged that the counterweightconstantly serves to urge the roll-engaging elements 26 into engagementwith the surface of roll i2. Likewise, one of the shafts has securedthereto a lever 3i by means of which the arms 2'! and 28 may be moved toan open position permittingready insertion of roll l2 andits shaft I Oneof the gears 29 meshes with a small pinion 32 on a shaft 33, this shaftlikewise bearing a sprocket 34 about which a chain 35 is trained, suchchain likewise passing over a second sprocket 36. Beneath one run of thesprocket chain a lever 31 is disposed, this lever being pivoted at 38 ata point adjacent one end thereof and at saidend being equipped with anadjustable tensioning means generally designated at 39. The long end orarm of the lever has engaged therewith a weighted roller 40 which islinked at 4| to sprocket chain 35 and it will be obvious that as thesprocket chain is shifted through rota- ;tion of arms 21 and 28 andcorresponding rotation of the shafts 2 5 and shaft 33 the effectiveweight imposed on the long arm of the lever will be .varied due tochange in position of the roller 40.

The numeral 42 designates a motor driven pump receiving its supply froma sump indicated at 43. The discharge line 44 leads to a simple four-wayvalve 45 such as that shown in Figure 4 through which the discharge maybe directed by conduit 44a or 44b either to the upper or lower end ofcylinder 20. An outlet line 45 from this four-way valve leads to sump43. The discharge line 44 from the pump is equipped with a by-pass meanstending to maintain said 41 having arranged therein apressure-regulating valve 48 the pressure control of which is varied inaccordance with the weighting of the long arm of lever 31. This valvemay be of any desired construction, a convenient form being illustratedin Figure 3. In this figure the valve proper, indicated at 48a, is shownas spring seated and as having at the upper end of its stem 48b a.roller 480 to engage the under surface of lever The casing 48d of thisvalve may conveniently include an arm 48c mounting the pivot for lever31. The extent of opening of the valve is determined by the pressureexerted through lever 31. This discharge line is likewise furtherprovided with a relief valve indicated at 49.

With a roll l2 newly placed in position, the position of the severalparts will be substantially as illustrated injFigure l of the drawings,pump 42 delivering pressure fluid to the upper end of cylinder 20(seeFigure 4) through valve 45 and conduit 44a. and it will be obviousthat as the diameter of the roll reduces roller 40will be shifted alonglever '31 to correspondingly vary the pressure exerted by piston IS onthe band brake. Due to the fact that two circumferentially spacedcontact elements are provided and these elements will always remainequidistant from the axis of roll I2, if the roll be flattened asindicated by dottedlines at l2a, this will not vary theposition ofroller 40, thus avoiding the oscillatory action 01 the pressure-applyingmemher which results when but a single arm is employed; When the roll isto be replaced, valve 45, which is manually actuated, may be shifted todeliver the pressure fluid to the lower end of the cylinder through line44b and exhaust the fluid from the upper end of the cylinder throughline 46. This will release the brake, permitting free running of gear 2|which is, obviously, necessary in installing the new roll and threadingthe sheet therefrom into the associated machine (not herein shown).

It will also be obvious that the construction illustrated is capable oi'considerable modification without departing from the spirit of myinvention.

I claim:

1. Means for controlling the tension of paper drawn from a roll rotatingabout a fixed axis comprising a brake for the roll and means to vary thetension of the brake in accordance with variation in diameter 01' theroll, said means including a shii'table member shifting of which variesthe braking resistance of the brake, a plurality of rollengagingelements adapted to engage the periphery o! the roll atcircumferentially spaced points,

elements in engagement with the roll, connections between said elementswhereby their roll-engaging portions are maintained at pointsequidistant from the axis of said roll and a connection between saidelements and said shiftable member constructed and arranged to positionsaid member in accordance with the position of said elements.

2. Means for controlling the tension of paper drawn from a roll rotatingabout a fixed axis comprising a brake for the roll, a plurality of rollengaging elements adapted to engage the periphery oi the roll atcircumferentially spaced points, means tending to maintain said elementsin engagement with the roll, connections between said elements wherebytheir roll-engaging portions are maintained at points equidistant fromthe axis of said roll and a connection between said elements and saidbrake constructed and arranged to vary the position of said brake inaccordance with the spacing of said elements from the axis of the roll.

3. Means for controlling the tension of paper drawn from a roll rotatingabout a fixed axis comprising a brake for the roll, a plurality ofroll-engaging elements adapted to engage the periphery of the roll atcircumferentially spaced points, means tending tomaintain said elementsin engagement with the roll, connections between said elements wherebytheir roll-engaging portions are maintained at points equidistant fromthe axis of said roll, a connection between said elements and said brakeconstructed and arranged to vary the position of said brake inaccordance with the spacing of said elements from the axis of the rollcomprising a fluid pressure cylinder having a piston the position ofwhich controls the position of said brake, and means to vary theposition of the piston in accordance with the position of said elements.

4. Means for controlling the tension of paper drawn from a roll rotatingabout a fixed axis comprising a brake for the roll, a plurality ofroll-engaging elements adapted to engage the periphery'of the roll atcircumferentially spaced points, means tending to maintain said elementsin engagement with the roll, connections between said elements wherebytheir roll-engaging portions are maintained at points equidistant fromthe axis of said roll and a connection between said elements and saidbrake constructed .and arranged to vary the position of said brake inaccordance with the'spacing of said elements from the axis of the rollcomprising a fluid pressure cylinder having a piston the position ofwhich controls the position ofsaid brake, and means to vary the positionof the piston in accordance with the position of saidelements, includinga pressure regulating valve and means to load said valve in accordancewith the position of said elements.

5. Means for controlling the tension of paper drawn from a roll rotatingabout a fixed axis comprising a brake for the roll, a plurality ofrollengaging elements adapted to engage the periphery of the roll atcircumferentially spaced points, means tending to maintain said elementsin engagement with the roll, connections between said elements wherebytheir roll-engaging portions are maintained at points equidistant fromthe axis of said roll and a connection between said elements and saidbrake constructed and arranged to vary the position of said brake inaccordance with thespacing of said elements from the axis of therollcomprising a fluid pressure cylinder having a piston the position ofwhich controls the position of said brake, and means to vary theposition of the piston in accordance with the position of said elementsincluding a pressure regulating valve, alever loading said valve andmeans to vary the lever loading in accordance with the position of saidelements.

CONRAD J. KERN.

